Abstract: Objective: To investigate the clinical application of 64-slice CT angiography in evaluating coronary atherosclerotic plaque. Method: Retrospectively collect 62 patients who diagnosed as coronary artery disease from June to September in 2009 in our hospital and divide them into two groups according to clinical manifestation, ACS (acute coronary syndromes) group and SAP (stable angina pectoris) group. We selected 100 segments in 100 blood vessels of coronary stenos is (≥ 50%) caused by atherosclerotic plaque with 64-slice CT angiography and discriminated the types of the plaques through axial view, CPR and MIP and measured the CT value of the plaques. Result: A hundred atherosclerotic plaques were evaluated with Schroeder’s two standards of CT value plaque-judging methods. The numbers of the three kinds of plaques by the two standards are highly accordant with 100% identity. The detection rate of non-calcified plaque in ACS group is apparently greater than in SAP group, and the detection rate of calcified plaque in SAP group is greater than in ACS group. There is statistical difference between the two groups (P<0.01). Conclusion: 64-slice MSCT can evaluate the nature of different types of plaque and detect unstable plaque in early stage. Non-calcified plaque is positively correlated with the risk of coronary artery disease.